Mitsubishi Electric FR-A840-00930 (37K) User Manual (English)

Questions and Answers:

J
Javier BestAug 17, 2025
What to do if hunting occurs in Mitsubishi Electric FR-A840-00930 (37K) Inverter motor?
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  jerry46Aug 17, 2025
  If hunting (vibration or acoustic noise) occurs in the motor or machine connected to your Mitsubishi Electric Inverter, it might be due to a speed control gain that is too high. Try performing easy gain tuning or setting Pr.820 lower and Pr.821 higher. Alternatively, the torque control gain could be too high. In this case, set Pr.824 Torque control P gain 1 (current loop proportional gain) lower. Finally, incorrect motor wiring can also cause this issue, so ensure that the wiring is correct.
T
Tyler PatrickAug 25, 2025
What to do if Mitsubishi Electric Inverter speed does not accelerate to the command speed?
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  Jonathan ReidAug 26, 2025
  If the speed of your Mitsubishi Electric Inverter does not accelerate to the command speed, it may be due to a torque shortage or the torque limit is operating. To resolve this, try raising the torque limit or increasing the capacity. Also, ensure that you are using PI control instead of only P (proportional) control.
S
sara06Aug 28, 2025
Why does Mitsubishi Electric Inverter motor speed fluctuate?
- S
  Steven HoltAug 29, 2025
  If the motor speed connected to your Mitsubishi Electric Inverter fluctuates, it could be due to several reasons. First, verify that the speed command sent from the controller is correct and implement EMC measures, and set Pr.72 lower. Another possible cause is a torque shortage, in which case you should raise the torque limit. If the speed control gain is not suitable for the machine, resulting in resonance, perform easy gain tuning.
W
William GregorySep 1, 2025
Why acceleration/deceleration time different from setting in Mitsubishi Electric Inverter?
- A
  Alicia EvansSep 2, 2025
  If the acceleration or deceleration time of your Mitsubishi Electric Inverter is different from the setting, it could be due to a torque shortage, so try raising the torque limit. Alternatively, the load inertia might be too high, therefore set acceleration/deceleration time suitable for the load.
P
Peter CisnerosSep 5, 2025
Why is machine movement unstable with Mitsubishi Electric Inverter?
- A
  Andrea GravesSep 5, 2025
  If the machine movement connected to your Mitsubishi Electric Inverter is unstable, it could be because the speed control gain is not suitable for the machine. Perform easy gain tuning to correct this. It could also be that the response is slow due to the inverter's acceleration/deceleration time setting, so set the optimum acceleration/deceleration time.
M
Mrs. Audrey DanielsSep 8, 2025
How to fix rotation ripple during low-speed operation in Mitsubishi Electric FR-A840-00930 (37K) Inverter?
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  Tony MccartySep 8, 2025
  If rotation ripple occurs during the low-speed operation of your Mitsubishi Electric Inverter, it might be due to a high carrier frequency affecting the motor rotation. Try setting Pr.72 lower. Another possible cause is that the speed control gain is too low, so try setting Pr.820 higher.

Mitsubishi Electric FR-A840-00930 (37K) Specifications

General

Brand	Mitsubishi Electric
Model	FR-A840-00930 (37K)
Category	Inverter
Language	English

Summary

MITSUBISHI ELECTRIC INVERTER FR-A800 INSTRUCTION MANUAL (DETAILED)

Chapter 1 INTRODUCTION

1.1 Product checking and accessories

Unpack the product and check the rating plate and the capacity plate of the inverter to ensure that the model agrees with the order and the product is intact.

Chapter 2 INSTALLATION AND WIRING

2.1 Peripheral devices

Check the model of the inverter you purchased. Appropriate peripheral devices must be selected according to the capacity.

2.2 Removal and reinstallation of the operation panel or the front covers

2.3 Installation of the inverter and enclosure design

Determines the structure, size, and device layout of the enclosure by fully considering the conditions such as heat generation and operating environment.